The following German-McClure model is also widely used [1]}, [2]}
\(\inf _{u \in X} F_{GM}(u ):=D(u)+ \frac{\mu }{2} \int _{\Omega }\frac{|\nabla u |^2/\lambda }{1+ |\nabla u |^2/\lambda }\mathrm {d}\sigma ,\) 
